Field of the Invention:
The invention relates to a gas-tight encapsulating enclosure having a sight glass for monitoring an encapsulating enclosure internal area for a power transmission device.
By way of example, utility model DE 298 06 211 U1 discloses a gas-tight encapsulating enclosure such as this. In this document, a combined isolating/grounding switch is arranged in an encapsulating housing internal area and has movable contact pieces. Sight glasses are incorporated in the encapsulating housing in order to identify the position of the movable contact pieces. The position of the movable contact pieces can be seen visually through these sight glasses.
Normally, the gas-tight encapsulating enclosure is manufactured from material through which optical radiation cannot pass. The encapsulating enclosure internal area is therefore shadowed. It is therefore possible to observe areas to be monitored in the encapsulating enclosure internal area only with difficulty.